Methylene Blue Absorption Tester By Controlled Micro Computer For Accurate Results

It is used to determinate the amount of methylene blue absorption and the the content of the effective bentonite in the bentonite.

It is a device that uses a microcomputer to control ultrasonic wave divergence and stirring of the test solution. The sample processing and stirring time are automatically controlled and displayed, and the time can be set arbitrarily by the microcomputer. Equipped with two sets of burettes, simultaneously controlling the titration of methylene blue titrant. The sample processing adopts ultrasonic dispersion method, which can quickly disperse the sample at room temperature. The measuring device is equipped with an automatic titrator and mechanically stirred. Mainly used to determine the blue absorption of bentonite and the effective bentonite content in molding sand (old sand), quickly and effectively detect the quality of bentonite to avoid surface defects on castings after use.

main specifications

Glass burette 25ml+25ml, ±1%

Blender speed: 1300r/min

timer range 1-99min.

Ultrasonic cleaner frequency: 40±2KHz

                Size: 177*167*200mm

Instrument features

1. Micro computer controls the ultrasonic wave and mixing the test solution.

2. Automaticly control and processing sample and the mixing time.

3. The sample can disperse quickly at normal temperature.

4. Through the detection, it can avoid forming defects on the surface of the casts. 

main applications

It is widely used in foundry, machinery, casting, qualitative inspection, scientific research, university lab.... 

Principle and structure of clay blue absorption tester

1. Principle

Bentonite in clay has a strong adsorption capacity for methylene blue. The size of this adsorption capacity depends on the type and origin of the bentonite, but it is also related to the degree of dispersion of the bentonite. Therefore, before measurement, the sample must be fully dispersed in order to accurately determine a large amount of blue absorption.

The use of ultrasonic dispersion treatment for bentonite samples is based on the fact that ultrasonic waves can cause "cavitation" in the liquid, which means that the liquid will produce many small "voids" in high-frequency ultrasonic waves. When these 'holes' grow to a certain size or are subjected to pressure waves, they will quickly burst. The instantaneous collapse of these voids can generate high temperature and pressure, causing local shock waves to form in the liquid, which has a strong dispersion effect. Therefore, pollutants or aggregated particles attached to the solid surface will be quickly separated. By utilizing this principle, the clay in the sample can be dispersed into small particles or peeled off from the surface of the sand particles, achieving sufficient dispersion.

When using titration to determine the blue absorption of a sample, mechanical stirring should be carried out simultaneously to allow the sample to fully contact methylene blue and undergo adsorption reaction. Titrate the sample suspension gradually with methylene blue solution and perform a drop test on filter paper. When free methylene blue begins to appear in the suspension, it is determined that the sample has reached saturation adsorption (titration reaches the "endpoint"), and thus the blue absorption of the sample can be measured.

2. Instrument structure

The methylene blue clay analyzer mainly consists of a sample dispersion device, a mechanical stirring and titration device. The two devices are their own and can work simultaneously, with a microcomputer controlling the dispersion processing and mixing time separately. Its structure is shown in the following figure:

(1) The sample dispersion device consists of an ultrasonic cleaner (ultrasonic disperser), accessories, and a timer. The ultrasonic cleaner (model MJ-50) is a small desktop all transistor circuit ultrasonic device that uses a pressure point ceramic material - aluminum zirconate titanate transducer. It has high conversion efficiency, good dispersion effect, low noise, and low power consumption. The ultrasonic cleaner can be used separately.

(2) Titration device

The automatic titrator has two automatic burettes, burette 1 and burette 2. The burette 1 is controlled by a "titration switch" and a high-performance anti-corrosion solenoid valve DZ1 to titrate methylene blue solution; Squeeze the glass beads with your hand to titrate the methylene blue solution using burette 2. When two types of burettes are used simultaneously, the milliliters of titrant must be read and added at the same time. The solution bottle can be a 500ML small mouth reagent bottle or a 1000mL small mouth reagent bottle. After adding methylene blue solution to the reagent bottle, the high-performance anti-corrosion solenoid valve DZ2 is controlled by the "liquid addition switch". The gas source pressurizes the solution bottle through DZ2 to simultaneously add methylene blue solution to burette 1 and burette 2. When the solution is filled to the burette. Release the "liquid addition switch", the solution returns to the solution bottle, and the titrant automatically resets to zero.

(3) Blender

The working time of the AC motor is controlled by a microcomputer, and the mixing shaft is connected by a coupling to thoroughly stir the test solution through a turbine blade.